1. Field of the Invention
The present invention relates to an upsizing adapter for electrically and mechanically coupling (a) a small size terminal electrode assembly having at least one ring electrode and a pin electrode and being situated at the proximal end of a pacing lead to (b) a large size terminal electrode assembly socket in a pacer having first and second electrical contacting means therein for contact with a ring electrode and pin electrode on a large size terminal electrode assembly.
2. Description of the Prior Art
Heretofore, various structures have been proposed for connecting a terminal pin assembly at the proximal end of a pacing lead assembly to a terminal pin assembly socket in a pacer.
For example, in U.S. Pat. No. 4,207,678, there is disclosed a connector for connecting a pin electrode to a pacer where the pacer with a socket therein and the pin electrode are derived from different manufacturers and are normally not adapted for connection one to another. The connector has a coil therein dimensioned to receive the pin electrode and has a smaller diameter pin extending therefrom for being received in the pacer socket. The connector is adapted to permit connection or disconnection as the connector is rotated.
In U.S. Pat. No. 4,259,962, there is disclosed, a tubular connector connected to the proximal end of a pacing lead assembly and having axially spaced inner and outer resilient rings for sealing engagement with the socket wall of a pacer neck.
In U.S. Pat. No. 4,226,244, there is disclosed, a preformed connector with an encapsulated terminal for attachment to a pacer. The preformed connector eliminates the use of epoxy or other similar substances to encapsulate the terminal after attachment of the terminal to the pacer.
Also, in U.S. Pat. No. 4,236,525, there is disclosed a proximal connector of a pacing lead assembly which connector is mounted in a socket in a pacer neck and is movable to change connections between contacts on the connector and contacts in the socket thereby to change the function of distal electrodes coupled by a pacing lead to the connector contacts.
As will be described in greater detail hereinafter, the upsizing adapter of the present invention differs from the structures disclosed in the patents referred to above by providing a structure for establishing both mechanical and electrical connections between a small size terminal electrode assembly located at the proximal end of a pacing lead assembly and having two electrodes and a large size terminal electrode assembly socket in a pacer having first and second electrical contacting means in the socket.